This is about the coolest cat toy and exercise machine ever ! You can see that the cats are all having a great time, and it is fun watching them, too.
This exercise wheel looks like a giant size hamster wheel,and it looks to me like the cats enjoy it every bit as much as a hamster or guinea pig does.
It has the little red light for the cat to chase, and since it is always in motion, the cat seems to keep on thinking that he can catch it if he just runs a little faster, or jumps a little higher.
Maybe not a practical thing spacewise, unless you have a room big enough to set it up for your cats though.
This video will certainly have you chuckling at the cats, in any case.